I thought that this would be easy after doing the
same job on the Mallard and on the 2-10-0 9F. How wrong I was. It was
a pain in the proverbial ........ The following sequence comes about
from having tried all sorts of other ways, and it involves something
that I don't like to do - bending. But unless you have another
suggestion - here goes....

First prepare the chassis. All of the wheels
should be in place, they should be aligned, and you may have the
coupling rod in place. I didn't. Take out the motor, and turn the
chassis upside down. Remove the front screw of the base plat, slacken
the rear, and slip out the front bogie. Don't disturb the wheels.
Screw the baseplate back up again.

Remove the cylinders. They slide off individually
from their respective side of the engine. You need to gently prise
the plastic tab over the raised metal 'lock'. Once clear, it just
pulls off.

Now - check if the rear of the gearbox will lift
up without having to pop out the gearbox axle. I didn't think it
would, so I pushed it out anyway. I've done it so many times now,
that it comes out quite easily.

Remove the con rod and the piston rod from the
valve gear assembly on each side. Rest the mechanism in place behind
the gearbox. Gently prise open a gap, and slide the valve assembly
underneath it into its locating slot. It should move freely left to
right for a few mm. Move it to the right as far as it will go.

I really hate doing this next bit, but I could
find no other option. I couldn't find any way that I could get all of
the valve gear into the respective locations at the same time,
without damaging something. I tried many times, without success. I
resorted to this method after a lot of swearing and cursing as the
valve gear repeatedly fell out of their locations. Maybe if you have
better eyesight, smaller fingers and 6 hands, you will succeed where
I failed. But this method works nicely, and you can focus on one side
at a time.

Gently. Very gently. Spring the right and left
hand side slider mechanisms outwards. This needs to be just enough to
clear one cylinder block when it is at the end of the metal beam. The
plan is to put the cylinder block onto the ends of the slider rods,
and then push the cylinders back onto the loco frame. For this side,
you can slide the valve gear over slightly to the right. But don't do
that yet !

First, lay the loco on its left side. Slide the
piston forward so that it sticks out further than the slide bars, and
insert the piston rod into the hole in the cylinder. Keeping the
piston in its hole, slide the plastic cylinder block onto the ends of
the slide bars. I needed a magnifying glass to see the tiny slots for
this. Be careful not to put any strain on the plastic slider as you
do this - you may need to let the slider and the piston move back as
you push the cylinder block onto the end of the slide bars.

Push the cylinder onto the beam. Before it
clicks, make sure that the conrod is still in the right position. If
not, manoevre it back into position before clicking the cylinder
block onto the frame.
Don't try to bend the valve gear back into shape
- once clicked, the cylinders will hold the gear against the
springiness. This is important. It would only take a few bends to
work harden the valve gear enough for it to snap off.

Fit the coupling rods, the push fit bolts on the
front and rear wheels.

Sorry about the out of sequence photo. I forgot
to take one at the time !

Put the eccentric crank into the hole of the con
rod, and manoevre the assembly into position so that the crank pin is
over the hole, and the eccentric rod coupling is almost over the axle
of the wheel. Push gently into place. Dont push it home yet though.

Now do the same with the other side. The valve
mechanism will not move across as far this time, so the slider rods
need to be bent a bit further. This could strain the plastic slider,
so keep an eye on it as you focus on getting the piston rod and the
slider rods into the holes in the plastic cylinder block.

The only time that there is risk of any strain,
is when you need to get the cylinder block over the end of the bar of
the frame. Move the slider and piston backwards as soon as possible
to reduce the risk of putting any strain on this. Push the cylinder
block down, but don't let it click home until you have checked that
the eccentric rod and con rod are in roughly the right position.

Locate the pins in the coupling rod and push them
loosely into place in the wheels. Pin slightly out of focus here, sorry.

Insert the eccentric coupling and con rod onto
the crankpin, locate the joint over the wheel axle, and press home loosely.

The engine is not in place, so give the chassis a
push around and watch the gear operating to check for any issues. (If
you removed the gearbox axle, make sure the gear is not in place
before you do this). If it is ok, push all of the pins home, and
check again.

Replace the bogie wheels, making sure that the
contact strip is correctly located. Keep your fingers firmly on the
wheels. If they pop out now, you may have to go back to the beginning!

Oh, and if you removed the gearbox axle, don't
forget to put it back !